In a magnetic memory with magnetoresistive effect elements, such as a spin torque transfer magnetic random access memory (STT-MRAM), the current necessary for the magnetization inversion of the magnetoresistive effect elements is defined by the current density. Namely, the magnetic memory has such scalability that the amount of current necessary for magnetization inversion decreases as the size of the magnetoresistive effect element decreases. By virtue of this feature, the magnetic memory is regarded as one of the major candidates for next-generation memories.
To put a magnetic memory with magnetoresistive effect elements into practical use, it is necessary to detect, by a test, a fail bit that does not satisfy the specifications, and to replace it with a pass bit that satisfies the specifications, using, for example, a redundancy technique. However, as it now stands, such a magnetic memory test method is not verified.